[Effect of salicylic acid on cell growth and polysaccharide production in suspension cultures of protocorm-like bodies from Dendrobium huoshanense].

Polysaccharides from Dendrobium huoshanense possess immunostimulating activity, antioxidant activity and anticataract activity. In order to produce the active polysaccharides from Dendrobium huoshanense through cell culture, we investigated the effects of salicylic acid on cell growth, accumulation of polysaccharides and utilization of carbon source in suspension cultures of protocorm-like bodies from Dendrobium huoshanense. Although salicylic acid slightly inhibited the cell growth, it was beneficial to the utilization of carbon source, thus leading to significant increase in the contents of polysaccharides. The highest polysaccharide production occurred on the medium supplied with 100 micromoI/L salicylic acid. After 18 days of culture the production of polysaccharides reached 3.129 g/L, which was 1.63 times that of the control. Further, we established the kinetic models describing cell growth, polysaccharide production and carbon source utilization based on Logistic equation, Luedeking-Piret equation and Luedeking-Piret-Like equation. The calculated values from the kinetic models showed a good fit to the experimental values, suggesting that salicylic acid could be an effective compound to enhance the production of active polysaccharides from protcorm-like bodies from Dendrobium huoshanense.